ALBERT

Description: 〈p〉By using click chemistry, a hexacationic cage was synthesized. The cage contains two triscationic -electron–deficient trispyridiniumtriazine (TPZ〈sup〉3+〈/sup〉) platforms that are bridged in a face-to-face manner by three ethylene-triazole-ethylene linkers. A diversity of -electron–rich guests can be recognized within the pocket of the cage, driven by host-guest - interactions. The cage cavity acts as a protecting group, preventing an anthracene guest from undergoing Diels-Alder reaction. Under ultraviolet (UV) light, the pyridinium CN bonds in TPZ〈sup〉3+〈/sup〉 platforms are polarized and weakened, resulting in the occurrence of cage decomposition via β-elimination. Guest recognition could help to prevent this UV-stimulated cage decomposition by suppressing the excitation of the TPZ〈sup〉3+〈/sup〉 units.〈/p〉

Description: Transferrin receptor facilitates TGF-β and BMP signaling activation to control craniofacial morphogenesis Cell Death and Disease 7, e2282 (June 2016). doi:10.1038/cddis.2016.170 Authors: R Lei, K Zhang, K Liu, X Shao, Z Ding, F Wang, Y Hong, M Zhu, H Li & H Li

Description: The interaction between active element Zr and W damages the W fibers and the interface and decreases the mechanical properties, especially the tensile strength of the W fibers reinforced Zr-based bulk metallic glass composites (BMGCs). From the viewpoint of atomic interaction, the W-Zr interaction can be restrained by adding minor elements that have stronger interaction with W into the alloy. The calculation about atomic interaction energy indicates that Ta and Nb preferred to segregate on the W substrate surface. Sessile drop experiment proves the prediction and corresponding in-situ coating appears at the interface. Besides, the atomic interaction mechanism was proven to be effective in many other systems by the sessile drop technique. Considering the interfacial morphology, Nb was added into the alloy to fabricate W/Zr-based BMGCs. As expected, the Nb addition effectively suppressed the W-Zr reaction and damage to W fibers. Both the compressive and tensile properties are improved obviously. Scientific Reports 5 doi: 10.1038/srep08967

Description: Antioxidants decrease the apoptotic effect of 5-Fu in colon cancer by regulating Src-dependent caspase-7 phosphorylation Cell Death and Disease 5, e983 (January 2014). doi:10.1038/cddis.2013.509 Authors: Y Fu, G Yang, F Zhu, C Peng, W Li, H Li, H-G Kim, A M Bode, Z Dong & Z Dong

Description: In this work, we investigate the bifurcations of relative equilibria in the gravitational potential of asteroids. A theorem concerning a conserved quantity, which is about the eigenvalues and number of relative equilibria, is presented and proved. The conserved quantity can restrict the number of non-degenerate equilibria in the gravitational potential of an asteroid. It is concluded that the number of non-degenerate equilibria in the gravitational field of an asteroid varies in pairs and is an odd number. In addition, the conserved quantity can also restrict the kinds of bifurcations of relative equilibria in the gravitational potential of an asteroid when the parameter varies. Furthermore, studies have shown that there exist transcritical bifurcations, quasi-transcritical bifurcations, saddle–node bifurcations, saddle–saddle bifurcations, binary saddle–node bifurcations, supercritical pitchfork bifurcations, and subcritical pitchfork bifurcations for the relative equilibria in the gravitational potential of asteroids. It is found that for the asteroid 216 Kleopatra, when the rotation period varies as a parameter, the number of relative equilibria changes from 7 to 5 to 3 to 1, and the bifurcations for the relative equilibria are saddle–node bifurcations and saddle–saddle bifurcations.

Description: Genome-wide association studies (GWAS) have identified several common loci contributing to non-obstructive azoospermia (NOA). However, a substantial fraction of NOA heritability remains undefined, especially those low-frequency [defined here as having a minor allele frequency (MAF) between 0.5 and 5%] and rare (MAF below 0.5%) variants. Here, we performed a 3-stage exome-wide association study in Han Chinese men to evaluate the role of low-frequency or rare germline variants in NOA development. The discovery stage included 962 NOA cases and 1348 healthy male controls genotyped by exome chips and was followed by a 2-stage replication with an additional 2168 cases and 5248 controls. We identified three low-frequency variants located at 6p22.2 (rs2298090 in HIST1H1E encoding p.Lys152Arg: OR = 0.30, P = 2.40 x 10 –16 ) and 6p21.33 (rs200847762 in FKBPL encoding p.Pro137Leu: OR = 0.11, P = 3.77 x 10 –16 ; rs11754464 in MSH5 : OR = 1.78, P = 3.71 x 10 –7 ) associated with NOA risk after Bonferroni correction. In summary, we report an instance of newly identified signals for NOA risk in genes previously undetected through GWAS on 6p22.2–6p21.33 in a Chinese population and highlight the role of low-frequency variants with a large effect in the process of spermatogenesis.

Description: PD-1 and Tim-3 pathways are associated with regulatory CD8+ T-cell function in decidua and maintenance of normal pregnancy Cell Death and Disease 6, e1738 (May 2015). doi:10.1038/cddis.2015.112 Authors: S-C Wang, Y-H Li, H-L Piao, X-W Hong, D Zhang, Y-Y Xu, Y Tao, Y Wang, M-M Yuan, D-J Li & M-R Du

Description: Understanding how gene regulation evolves is a key area in the current evolutionary field. Gene regulation occurs at various levels. Previous work on the evolution of gene regulation has largely focused on gene transcription. In this study, we used a recently developed ribosomal footprint profiling method to investigate how gene regulation evolves at both the transcription (mRNA abundance) and translation (ribosomal density) levels. By constructing a hybrid between Saccharomyces cerevisiae (Scer) and Saccharomyces bayanus (Sbay), which diverged ~20 Ma, and quantifying transcriptome and translatome in both parental strains and their hybrid, we showed that translation is much more conserved than transcription, mostly due to the buffering effect of translational regulation for the transcriptional divergence. More conservation in translation than transcription is also confirmed by the inheritance mode of transcription and translation between two species. Furthermore, cis and trans effects are widely involved in changes at both transcription and translation levels. Finally, our results showed that genes with certain functions and sequence features might employ specific modes for evolution at these two critical levels of gene regulation. Our results demonstrated that it is essential to investigate the evolution of gene regulation at various levels from different genetic backgrounds to obtain a complete picture of its evolutionary modes in nature.

Description: The electrical conductivity of gabbro was investigated at 623–1173 K, 0.5–2.0 GPa and oxygen fugacities controlled by three solid buffers (Cu + CuO, Ni + NiO and Mo + MoO 2 ) using a YJ-3000t multianvil press and Solartron-1260 impedance spectroscopy analyzer within the frequency range 10 –1 –10 6 Hz. The measured electrical conductivity shows an Arrhenius increase with temperature and increases with increasing pressure. The activation energy and activation volume of charge carriers have been determined as 0.72±0.01 eV and –6.8 ± 0.69 cm 3 /mol, respectively. The hydrogen-assisted electrical conductivity in gabbro decreases with increasing oxygen fugacity. Furthermore, it is inferred that some hydrogen-related defects with minor concentration ( e.g. , H' M or H • ) are the main charge carriers in the sample and provide reasonable explanations for the behavior of electrical conductivity of gabbro at high pressure.

Description: Early Cambrian black shale and chert in the Qinling-Daba region along the northern margin of the Yangtze (South China) craton host important high-grade strata-bound barite and witherite deposits. Barite-dominated deposits occur in a northern thrust domain, whereas witherite-dominated deposits occur in a thrust domain a few tens of km to the southwest. The authors studied the strontium isotope ( 87 Sr/ 86 Sr), and stable isotope composition ( 34 S, 13 C, and 18 O) of barite and witherite from the Shenxiantai and Chiyan deposits, two representative Ba deposits in the region, and compared these data to previously reported Sr, S, C, and O isotope data on a variety of Ba deposits in a similar stratigraphic position along the Early Cambrian rifted margin of the Yangtze craton. Most barite and witherite deposits in the Qinling-Daba region have consistent 87 Sr/ 86 Sr ratios with an average value of 0.70845 ± 0.00017 (1 , n = 53), in the range of Early Cambrian seawater from 0.7081 to 0.7090. Barite 34 S and 18 O VSMOW values vary from 8.0 to 76.1 (avg 40.6 ± 13.2, 1 , n = 35) and from 9.9 to 24.7 (avg 19.0 ± 3.0, 1 , n = 103), respectively, generally higher than those of seawater sulfate in the Early Cambrian. We propose that seawater-derived barium was precipitated in the anoxic water column and during early diagenesis. Bacterial sulfate reduction (BSR) and reoxidation under partial sulfate limitation produced higher 34 S and 18 O values of the diagenetic barite compared to contemporaneous seawater sulfate. The 13 C values of Ba carbonate minerals (witherite and barytocalcite) vary from –10.8 to –23.6 (avg –14.1 ± 3.2, 1 , n = 84) and indicate the involvement of carbon from oxidized organic matter. Although the 87 Sr/ 86 Sr ratios, 34 S, and 13 C values of barite and witherite are very close, barite has slightly higher 18 O VSMOW values (avg 22.0 ± 1.6, 1 , n = 19) than witherite and barytocalcite (avg 18.0 ± 2.5, 1 , n = 84), possibly revealing the role of CO 2 -rich cold seeps under sulfate-limited sedimentary-diagenetic conditions during the formation of the witherite-dominated deposits. The Sr isotope composition of barite in the Shenxiantai deposit is different from the other barite deposits and has lower 87 Sr/ 86 Sr ratios, which suggests the involvement of less radiogenic Sr in diagenetic fluids which interacted with underlying mafic volcanic rocks.